Reading heartbeat data from lowest node rather than from zero, in cases
where the node is not defined from zero, can reduce the number of sectors
read.
Here is a simple test data obtained with 'iostat -dmx dm-5 2', with
two nodes in the cluster, node number 10, 20, respectively.
Before optimization:
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
dm-5 0.00 0.00 0.50 0.50 0.01 0.00 11.00 0.00 1.00 1.00 1.00 1.50 0.15
After the optimization:
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
dm-5 0.00 0.00 0.50 0.50 0.00 0.00 6.00 0.00 0.50 1.00 0.00 0.50 0.05
Link: http://lkml.kernel.org/r/99fe4988-69ac-3615-a218-3042fe6fbe72@huawei.com
Signed-off-by: Jia Guo <guojia12@huawei.com>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull file locking updates from Jeff Layton:
"The main change in this set is Neil Brown's work to reduce the
thundering herd problem when a heavily-contended file lock is
released.
Previously we'd always wake up all waiters when this occurred. With
this set, we'll now we only wake up waiters that were blocked on the
range being released"
* tag 'locks-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
locks: Use inode_is_open_for_write
fs/locks: remove unnecessary white space.
fs/locks: merge posix_unblock_lock() and locks_delete_block()
fs/locks: create a tree of dependent requests.
fs/locks: change all *_conflict() functions to return bool.
fs/locks: always delete_block after waiting.
fs/locks: allow a lock request to block other requests.
fs/locks: use properly initialized file_lock when unlocking.
ocfs2: properly initial file_lock used for unlock.
gfs2: properly initial file_lock used for unlock.
NFS: use locks_copy_lock() to copy locks.
fs/locks: split out __locks_wake_up_blocks().
fs/locks: rename some lists and pointers.
Pull ext4 updates from Ted Ts'o:
"All cleanups and bug fixes; most notably, fix some problems discovered
in ext4's NFS support, and fix an ioctl (EXT4_IOC_GROUP_ADD) used by
old versions of e2fsprogs which we accidentally broke a while back.
Also fixed some error paths in ext4's quota and inline data support.
Finally, improve tail latency in jbd2's commit code"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: check for shutdown and r/o file system in ext4_write_inode()
ext4: force inode writes when nfsd calls commit_metadata()
ext4: avoid declaring fs inconsistent due to invalid file handles
ext4: include terminating u32 in size of xattr entries when expanding inodes
ext4: compare old and new mode before setting update_mode flag
ext4: fix EXT4_IOC_GROUP_ADD ioctl
ext4: hard fail dax mount on unsupported devices
jbd2: update locking documentation for transaction_t
ext4: remove redundant condition check
jbd2: clean up indentation issue, replace spaces with tab
ext4: clean up indentation issues, remove extraneous tabs
ext4: missing unlock/put_page() in ext4_try_to_write_inline_data()
ext4: fix possible use after free in ext4_quota_enable
jbd2: avoid long hold times of j_state_lock while committing a transaction
ext4: add ext4_sb_bread() to disambiguate ENOMEM cases
Pull iomap update from Darrick Wong:
"Fix a memory overflow bug for blocksize < pagesize"
* tag 'iomap-4.21-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: don't search past page end in iomap_is_partially_uptodate
Pull XFS updates from Darrick Wong:
- Fix CoW remapping of extremely fragmented file areas
- Fix a zero-length symlink verifier error
- Constify some of the rmap owner structures for per-AG metadata
- Precalculate inode geometry for later use
- Fix scrub counting problems
- Don't crash when rtsummary inode is null
- Fix x32 ioctl operation
- Fix enum->string mappings for ftrace output
- Cache realtime summary information in memory
* tag 'xfs-4.21-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (24 commits)
xfs: reallocate realtime summary cache on growfs
xfs: stringify scrub types in ftrace output
xfs: stringify btree cursor types in ftrace output
xfs: move XFS_INODE_FORMAT_STR mappings to libxfs
xfs: move XFS_AG_BTREE_CMP_FORMAT_STR mappings to libxfs
xfs: fix symbolic enum printing in ftrace output
xfs: fix function pointer type in ftrace format
xfs: Fix x32 ioctls when cmd numbers differ from ia32.
xfs: Fix bulkstat compat ioctls on x32 userspace.
xfs: Align compat attrlist_by_handle with native implementation.
xfs: require both realtime inodes to mount
xfs: cache minimum realtime summary level
xfs: count inode blocks correctly in inobt scrub
xfs: precalculate cluster alignment in inodes and blocks
xfs: precalculate inodes and blocks per inode cluster
xfs: add a block to inode count converter
xfs: remove xfs_rmap_ag_owner and friends
xfs: const-ify xfs_owner_info arguments
xfs: streamline defer op type handling
xfs: idiotproof defer op type configuration
...
Pull ext2, udf, and quota update from Jan Kara:
"Some ext2 cleanups, a fix for UDF crash on corrupted media, and one
quota locking fix"
* tag 'fs_for_4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
udf: Fix BUG on corrupted inode
ext2: change reusable parameter to true when calling mb_cache_entry_create()
ext2: remove redundant condition check
ext2: avoid unnecessary operation in ext2_error()
Pull fsnotify updates from Jan Kara:
"Support for new FAN_OPEN_EXEC event and couple of cleanups around
fsnotify"
* tag 'fsnotify_for_v4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fanotify: Use inode_is_open_for_write
fanotify: Make sure to check event_len when copying
fsnotify/fdinfo: include fdinfo.h for inotify_show_fdinfo()
fanotify: introduce new event mask FAN_OPEN_EXEC_PERM
fsnotify: refactor fsnotify_parent()/fsnotify() paired calls when event is on path
fanotify: introduce new event mask FAN_OPEN_EXEC
fanotify: return only user requested event types in event mask
Pull dlm updates from David Teigland:
"This set is entirely trivial fixes, mainly around correct cleanup on
error paths and improved error checks. One patch adds scheduling in a
potentially long recovery loop"
* tag 'dlm-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: fix invalid cluster name warning
dlm: NULL check before some freeing functions is not needed
dlm: NULL check before kmem_cache_destroy is not needed
dlm: fix missing idr_destroy for recover_idr
dlm: memory leaks on error path in dlm_user_request()
dlm: lost put_lkb on error path in receive_convert() and receive_unlock()
dlm: possible memory leak on error path in create_lkb()
dlm: fixed memory leaks after failed ls_remove_names allocation
dlm: fix possible call to kfree() for non-initialized pointer
dlm: Don't swamp the CPU with callbacks queued during recovery
dlm: don't leak kernel pointer to userspace
dlm: don't allow zero length names
dlm: fix invalid free
Pull btrfs updates from David Sterba:
"New features:
- swapfile support - after a long time it's here, with some
limitations where COW design does not work well with the swap
implementation (nodatacow file, no compression, cannot be
snapshotted, not possible on multiple devices, ...), as this is the
most restricted but working setup, we'll try to improve that in the
future
- metadata uuid - an optional incompat feature to assign a new
filesystem UUID without overwriting all metadata blocks, stored
only in superblock
- more balance messages are printed to system log, initial is in the
format of the command line that would be used to start it
Fixes:
- tag pages of a snapshot to better separate pages that are involved
in the snapshot (and need to get synced) from newly dirtied pages
that could slow down or even livelock the snapshot operation
- improved check of filesystem id associated with a device during
scan to detect duplicate devices that could be mixed up during
mount
- fix device replace state transitions, eg. when it ends up
interrupted and reboot tries to restart balance too, or when
start/cancel ioctls race
- fix a crash due to a race when quotas are enabled during snapshot
creation
- GFP_NOFS/memalloc_nofs_* fixes due to GFP_KERNEL allocations in
transaction context
- fix fsync of files with multiple hard links in new directories
- fix race of send with transaction commits that create snapshots
Core changes:
- cleanups:
* further removals of now-dead fsync code
* core function for finding free extent has been split and
provides a base for further cleanups to make the logic more
understandable
* removed lot of indirect callbacks for data and metadata inodes
* simplified refcounting and locking for cloned extent buffers
* removed redundant function arguments
* defines converted to enums where appropriate
- separate reserve for delayed refs from global reserve, update logic
to do less trickery and ad-hoc heuristics, move out some related
expensive operations from transaction commit or file truncate
- dev-replace switched from custom locking scheme to semaphore
- remove first phase of balance that tried to make some space for the
relocation by calling shrink and grow, this did not work as
expected and only introduced more error states due to potential
resize failures, slightly improves the runtime as the chunks on all
devices are not needlessly enumerated
- clone and deduplication now use generic helper that adds a few more
checks that were missing from the original btrfs implementation of
the ioctls"
* tag 'for-4.21-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (125 commits)
btrfs: Fix typos in comments and strings
btrfs: improve error handling of btrfs_add_link
Btrfs: use generic_remap_file_range_prep() for cloning and deduplication
btrfs: Refactor main loop in extent_readpages
btrfs: Remove 1st shrink/grow phase from balance
Btrfs: send, fix race with transaction commits that create snapshots
Btrfs: use nofs context when initializing security xattrs to avoid deadlock
btrfs: run delayed items before dropping the snapshot
btrfs: catch cow on deleting snapshots
btrfs: extent-tree: cleanup one-shot usage of @blocksize in do_walk_down
Btrfs: scrub, move setup of nofs contexts higher in the stack
btrfs: scrub: move scrub_setup_ctx allocation out of device_list_mutex
btrfs: scrub: pass fs_info to scrub_setup_ctx
btrfs: fix truncate throttling
btrfs: don't run delayed refs in the end transaction logic
btrfs: rework btrfs_check_space_for_delayed_refs
btrfs: add new flushing states for the delayed refs rsv
btrfs: update may_commit_transaction to use the delayed refs rsv
btrfs: introduce delayed_refs_rsv
btrfs: only track ref_heads in delayed_ref_updates
...
Pull gfs2 updates from Bob Peterson:
- Enhancements and performance improvements to journal replay (Abhi
Das)
- Cleanup of gfs2_is_ordered and gfs2_is_writeback (Andreas
Gruenbacher)
- Fix a potential double-free in inode creation (Andreas Gruenbacher)
- Fix the bitmap search loop that was searching too far (Andreas
Gruenbacher)
- Various cleanups (Andreas Gruenbacher, Bob Peterson)
- Implement Steve Whitehouse's patch to dump nrpages for inodes (Bob
Peterson)
- Fix a withdraw bug where stuffed journaled data files didn't allocate
enough journal space to be grown (Bob Peterson)
* tag 'gfs2-4.21.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: take jdata unstuff into account in do_grow
gfs2: Dump nrpages for inodes and their glocks
gfs2: Fix loop in gfs2_rbm_find
gfs2: Get rid of potential double-freeing in gfs2_create_inode
gfs2: Remove vestigial bd_ops
gfs2: read journal in large chunks to locate the head
gfs2: add a helper function to get_log_header that can be used elsewhere
gfs2: changes to gfs2_log_XXX_bio
gfs2: add more timing info to journal recovery process
gfs2: Fix the gfs2_invalidatepage description
gfs2: Clean up gfs2_is_{ordered,writeback}
Pull crypto updates from Herbert Xu:
"API:
- Add 1472-byte test to tcrypt for IPsec
- Reintroduced crypto stats interface with numerous changes
- Support incremental algorithm dumps
Algorithms:
- Add xchacha12/20
- Add nhpoly1305
- Add adiantum
- Add streebog hash
- Mark cts(cbc(aes)) as FIPS allowed
Drivers:
- Improve performance of arm64/chacha20
- Improve performance of x86/chacha20
- Add NEON-accelerated nhpoly1305
- Add SSE2 accelerated nhpoly1305
- Add AVX2 accelerated nhpoly1305
- Add support for 192/256-bit keys in gcmaes AVX
- Add SG support in gcmaes AVX
- ESN for inline IPsec tx in chcr
- Add support for CryptoCell 703 in ccree
- Add support for CryptoCell 713 in ccree
- Add SM4 support in ccree
- Add SM3 support in ccree
- Add support for chacha20 in caam/qi2
- Add support for chacha20 + poly1305 in caam/jr
- Add support for chacha20 + poly1305 in caam/qi2
- Add AEAD cipher support in cavium/nitrox"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (130 commits)
crypto: skcipher - remove remnants of internal IV generators
crypto: cavium/nitrox - Fix build with !CONFIG_DEBUG_FS
crypto: salsa20-generic - don't unnecessarily use atomic walk
crypto: skcipher - add might_sleep() to skcipher_walk_virt()
crypto: x86/chacha - avoid sleeping under kernel_fpu_begin()
crypto: cavium/nitrox - Added AEAD cipher support
crypto: mxc-scc - fix build warnings on ARM64
crypto: api - document missing stats member
crypto: user - remove unused dump functions
crypto: chelsio - Fix wrong error counter increments
crypto: chelsio - Reset counters on cxgb4 Detach
crypto: chelsio - Handle PCI shutdown event
crypto: chelsio - cleanup:send addr as value in function argument
crypto: chelsio - Use same value for both channel in single WR
crypto: chelsio - Swap location of AAD and IV sent in WR
crypto: chelsio - remove set but not used variable 'kctx_len'
crypto: ux500 - Use proper enum in hash_set_dma_transfer
crypto: ux500 - Use proper enum in cryp_set_dma_transfer
crypto: aesni - Add scatter/gather avx stubs, and use them in C
crypto: aesni - Introduce partial block macro
..
Pull pstore updates from Kees Cook:
"Improvements and refactorings:
- Improve compression handling
- Refactor argument handling during initialization
- Avoid needless locking for saner EFI backend handling
- Add more kern-doc and improve debugging output"
* tag 'pstore-v4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Avoid NULL deref in ftrace merging failure path
pstore: Convert buf_lock to semaphore
pstore: Fix bool initialization/comparison
pstore/ram: Do not treat empty buffers as valid
pstore/ram: Simplify ramoops_get_next_prz() arguments
pstore: Map PSTORE_TYPE_* to strings
pstore: Replace open-coded << with BIT()
pstore: Improve and update some comments and status output
pstore/ram: Add kern-doc for struct persistent_ram_zone
pstore/ram: Report backend assignments with finer granularity
pstore/ram: Standardize module name in ramoops
pstore: Avoid duplicate call of persistent_ram_zap()
pstore: Remove needless lock during console writes
pstore: Do not use crash buffer for decompression
Pull RCU updates from Ingo Molnar:
"The biggest RCU changes in this cycle were:
- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.
- Replace calls of RCU-bh and RCU-sched update-side functions to
their vanilla RCU counterparts. This series is a step towards
complete removal of the RCU-bh and RCU-sched update-side functions.
( Note that some of these conversions are going upstream via their
respective maintainers. )
- Documentation updates, including a number of flavor-consolidation
updates from Joel Fernandes.
- Miscellaneous fixes.
- Automate generation of the initrd filesystem used for rcutorture
testing.
- Convert spin_is_locked() assertions to instead use lockdep.
( Note that some of these conversions are going upstream via their
respective maintainers. )
- SRCU updates, especially including a fix from Dennis Krein for a
bag-on-head-class bug.
- RCU torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
rcutorture: Don't do busted forward-progress testing
rcutorture: Use 100ms buckets for forward-progress callback histograms
rcutorture: Recover from OOM during forward-progress tests
rcutorture: Print forward-progress test age upon failure
rcutorture: Print time since GP end upon forward-progress failure
rcutorture: Print histogram of CB invocation at OOM time
rcutorture: Print GP age upon forward-progress failure
rcu: Print per-CPU callback counts for forward-progress failures
rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings
rcutorture: Dump grace-period diagnostics upon forward-progress OOM
rcutorture: Prepare for asynchronous access to rcu_fwd_startat
torture: Remove unnecessary "ret" variables
rcutorture: Affinity forward-progress test to avoid housekeeping CPUs
rcutorture: Break up too-long rcu_torture_fwd_prog() function
rcutorture: Remove cbflood facility
torture: Bring any extra CPUs online during kernel startup
rcutorture: Add call_rcu() flooding forward-progress tests
rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
tools/kernel.h: Replace synchronize_sched() with synchronize_rcu()
net/decnet: Replace rcu_barrier_bh() with rcu_barrier()
...
Pull sparc updates from David Miller:
- Automatic system call table generation, from Firoz Khan.
- Clean up accesses to the OF device names by using full_name instead
of path_component_name.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
ALSA: sparc: Use of_node_name_eq for node name comparisons
sbus: Use of_node_name_eq for node name comparisons
sparc: generate uapi header and system call table files
sparc: add system call table generation support
sparc: add __NR_syscalls along with NR_syscalls
sparc: move __IGNORE* entries to non uapi header
sparc: Use DT node full_name instead of name for resources
sparc: Remove unused leon_trans_init
sparc: Use device_type helpers to access the node type
sparc: Use of_node_name_eq for node name comparisons
sparc: Convert to using %pOFn instead of device_node.name
sparc: prom: use property "name" directly to construct node names
of: Drop full path from full_name for PDT systems
sparc: Convert to using %pOF instead of full_name
fs/openpromfs: Use of_node_name_eq for node name comparisons
fs/openpromfs: use full_name instead of path_component_name
Pull mtd updates from Boris Brezillon:
"SPI NOR Core changes:
- Parse the 4BAIT SFDP section
- Add a bunch of SPI NOR entries to the flash_info table
- Add the concept of SFDP fixups and use it to fix a bug on MX25L25635F
- A bunch of minor cleanups/comestic changes
NAND core changes:
- kernel-doc miscellaneous fixes.
- Third batch of fixes/cleanup to the raw NAND core impacting various
controller drivers (ams-delta, marvell, fsmc, denali, tegra,
vf610):
* Stop to pass mtd_info objects to internal functions
* Reorganize code to avoid forward declarations
* Drop useless test in nand_legacy_set_defaults()
* Move nand_exec_op() to internal.h
* Add nand_[de]select_target() helpers
* Pass the CS line to be selected in struct nand_operation
* Make ->select_chip() optional when ->exec_op() is implemented
* Deprecate the ->select_chip() hook
* Move the ->exec_op() method to nand_controller_ops
* Move ->setup_data_interface() to nand_controller_ops
* Deprecate the dummy_controller field
* Fix JEDEC detection
* Provide a helper for polling GPIO R/B pin
Raw NAND chip drivers changes:
- Macronix:
* Flag 1.8V AC chips with a broken GET_FEATURES(TIMINGS)
Raw NAND controllers drivers changes:
- Ams-delta:
* Fix the error path
* SPDX tag added
* May be compiled with COMPILE_TEST=y
* Conversion to ->exec_op() interface
* Drop .IOADDR_R/W use
* Use GPIO API for data I/O
- Denali:
* Remove denali_reset_banks()
* Remove ->dev_ready() hook
* Include <linux/bits.h> instead of <linux/bitops.h>
* Changes to comply with the above fixes/cleanup done in the core.
- FSMC:
* Add an SPDX tag to replace the license text
* Make conversion from chip to fsmc consistent
* Fix unchecked return value in fsmc_read_page_hwecc
* Changes to comply with the above fixes/cleanup done in the core.
- Marvell:
* Prevent timeouts on a loaded machine (fix)
* Changes to comply with the above fixes/cleanup done in the core.
- OMAP2:
* Pass the parent of pdev to dma_request_chan() (fix)
- R852:
* Use generic DMA API
- sh_flctl:
* Convert to SPDX identifiers
- Sunxi:
* Write pageprog related opcodes to the right register: WCMD_SET (fix)
- Tegra:
* Stop implementing ->select_chip()
- VF610:
* Add an SPDX tag to replace the license text
* Changes to comply with the above fixes/cleanup done in the core.
- Various trivial/spelling/coding style fixes.
SPI-NAND drivers changes:
- Remove the depreacated mt29f_spinand driver from staging.
- Add support for:
* Toshiba TC58CVG2S0H
* GigaDevice GD5FxGQ4xA
* Winbond W25N01GV
JFFS2 changes:
- Fix a lockdep issue
MTD changes:
- Rework the physmap driver to merge gpio-addr-flash and physmap_of
in it
- Add a new compatible for RedBoot partitions
- Make sub-partitions RW if the parent partition was RO because of a
mis-alignment
- Add pinctrl support to the
- Addition of /* fall-through */ comments where appropriate
- Various minor fixes and cleanups
Other changes:
- Update my email address"
* tag 'mtd/for-4.21' of git://git.infradead.org/linux-mtd: (108 commits)
mtd: rawnand: sunxi: Write pageprog related opcodes to WCMD_SET
MAINTAINERS: Update my email address
mtd: rawnand: marvell: prevent timeouts on a loaded machine
mtd: rawnand: omap2: Pass the parent of pdev to dma_request_chan()
mtd: rawnand: Fix JEDEC detection
mtd: spi-nor: Add support for is25lp016d
mtd: spi-nor: parse SFDP 4-byte Address Instruction Table
mtd: spi-nor: Add 4B_OPCODES flag to is25lp256
mtd: spi-nor: Add an SPDX tag to spi-nor.{c,h}
mtd: spi-nor: Make the enable argument passed to set_byte() a bool
mtd: spi-nor: Stop passing flash_info around
mtd: spi-nor: Avoid forward declaration of internal functions
mtd: spi-nor: Drop inline on all internal helpers
mtd: spi-nor: Add a post BFPT fixup for MX25L25635E
mtd: spi-nor: Add a post BFPT parsing fixup hook
mtd: spi-nor: Add the SNOR_F_4B_OPCODES flag
mtd: spi-nor: cast to u64 to avoid uint overflows
mtd: spi-nor: Add support for IS25LP032/064
mtd: spi-nor: add entry for mt35xu512aba flash
mtd: spi-nor: add macros related to MICRON flash
...
Pull vfs fixes from Al Viro:
"A couple of fixes - no common topic ;-)"
[ The aio spectre patch also came in from Jens, so now we have that
doubly fixed .. ]
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
proc/sysctl: don't return ENOMEM on lookup when a table is unregistering
aio: fix spectre gadget in lookup_ioctx
This reverts commit 55956b59df.
commit 55956b59df ("vfs: Allow userns root to call mknod on owned filesystems.")
enabled mknod() in user namespaces for userns root if CAP_MKNOD is
available. However, these device nodes are useless since any filesystem
mounted from a non-initial user namespace will set the SB_I_NODEV flag on
the filesystem. Now, when a device node s created in a non-initial user
namespace a call to open() on said device node will fail due to:
bool may_open_dev(const struct path *path)
{
return !(path->mnt->mnt_flags & MNT_NODEV) &&
!(path->mnt->mnt_sb->s_iflags & SB_I_NODEV);
}
The problem with this is that as of the aforementioned commit mknod()
creates partially functional device nodes in non-initial user namespaces.
In particular, it has the consequence that as of the aforementioned commit
open() will be more privileged with respect to device nodes than mknod().
Before it was the other way around. Specifically, if mknod() succeeded
then it was transparent for any userspace application that a fatal error
must have occured when open() failed.
All of this breaks multiple userspace workloads and a widespread assumption
about how to handle mknod(). Basically, all container runtimes and systemd
live by the slogan "ask for forgiveness not permission" when running user
namespace workloads. For mknod() the assumption is that if the syscall
succeeds the device nodes are useable irrespective of whether it succeeds
in a non-initial user namespace or not. This logic was chosen explicitly
to allow for the glorious day when mknod() will actually be able to create
fully functional device nodes in user namespaces.
A specific problem people are already running into when running 4.18 rc
kernels are failing systemd services. For any distro that is run in a
container systemd services started with the PrivateDevices= property set
will fail to start since the device nodes in question cannot be
opened (cf. the arguments in [1]).
Full disclosure, Seth made the very sound argument that it is already
possible to end up with partially functional device nodes. Any filesystem
mounted with MS_NODEV set will allow mknod() to succeed but will not allow
open() to succeed. The difference to the case here is that the MS_NODEV
case is transparent to userspace since it is an explicitly set mount option
while the SB_I_NODEV case is an implicit property enforced by the kernel
and hence opaque to userspace.
[1]: https://github.com/systemd/systemd/pull/9483
Signed-off-by: Christian Brauner <christian@brauner.io>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At mount time, we allocate m_rsum_cache with the number of realtime
bitmap blocks. However, xfs_growfs_rt() can increase the number of
realtime bitmap blocks. Using the cache after this happens may access
out of the bounds of the cache. Fix it by reallocating the cache in this
case.
Fixes: 355e353213 ("xfs: cache minimum realtime summary level")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Pull smb3 fix from Steve French:
"An important smb3 fix for an regression to some servers introduced by
compounding optimization to rmdir.
This fix has been tested by multiple developers (including me) with
the usual private xfstesting, but also by the new cifs/smb3 "buildbot"
xfstest VMs (thank you Ronnie and Aurelien for good work on this
automation). The automated testing has been updated so that it will
catch problems like this in the future.
Note that Pavel discovered (very recently) some unrelated but
extremely important bugs in credit handling (smb3 flow control problem
that can lead to disconnects/reconnects) when compounding, that I
would have liked to send in ASAP but the complete testing of those two
fixes may not be done in time and have to wait for 4.21"
* tag '4.20-rc7-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: Fix rmdir compounding regression to strict servers
iomap_is_partially_uptodate() is intended to check wither blocks within
the selected range of a not-uptodate page are uptodate; if the range we
care about is up to date, it's an optimization.
However, the iomap implementation continues to check all blocks up to
from+count, which is beyond the page, and can even be well beyond the
iop->uptodate bitmap.
I think the worst that will happen is that we may eventually find a zero
bit and return "not partially uptodate" when it would have otherwise
returned true, and skip the optimization. Still, it's clearly an invalid
memory access that must be fixed.
So: fix this by limiting the search to within the page as is done in the
non-iomap variant, block_is_partially_uptodate().
Zorro noticed thiswhen KASAN went off for 512 byte blocks on a 64k
page system:
BUG: KASAN: slab-out-of-bounds in iomap_is_partially_uptodate+0x1a0/0x1e0
Read of size 8 at addr ffff800120c3a318 by task fsstress/22337
Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Pull UBI/UBIFS fixes from Richard Weinberger:
- Kconfig dependency fixes for our new auth feature
- Fix for selecting the right compressor when creating a fs
- Bugfix for a bug in UBIFS's O_TMPFILE implementation
- Refcounting fixes for UBI
* tag 'upstream-4.20-rc7' of git://git.infradead.org/linux-ubifs:
ubifs: Handle re-linking of inodes correctly while recovery
ubi: Do not drop UBI device reference before using
ubi: Put MTD device after it is not used
ubifs: Fix default compression selection in ubifs
ubifs: Fix memory leak on error condition
ubifs: auth: Add CONFIG_KEYS dependency
ubifs: CONFIG_UBIFS_FS_AUTHENTICATION should depend on UBIFS_FS
ubifs: replay: Fix high stack usage
This reverts commit 61c6de6672.
The reverted commit added page reference counting to iomap page
structures that are used to track block size < page size state. This
was supposed to align the code with page migration page accounting
assumptions, but what it has done instead is break XFS filesystems.
Every fstests run I've done on sub-page block size XFS filesystems
has since picking up this commit 2 days ago has failed with bad page
state errors such as:
# ./run_check.sh "-m rmapbt=1,reflink=1 -i sparse=1 -b size=1k" "generic/038"
....
SECTION -- xfs
FSTYP -- xfs (debug)
PLATFORM -- Linux/x86_64 test1 4.20.0-rc6-dgc+
MKFS_OPTIONS -- -f -m rmapbt=1,reflink=1 -i sparse=1 -b size=1k /dev/sdc
MOUNT_OPTIONS -- /dev/sdc /mnt/scratch
generic/038 454s ...
run fstests generic/038 at 2018-12-20 18:43:05
XFS (sdc): Unmounting Filesystem
XFS (sdc): Mounting V5 Filesystem
XFS (sdc): Ending clean mount
BUG: Bad page state in process kswapd0 pfn:3a7fa
page:ffffea0000ccbeb0 count:0 mapcount:0 mapping:ffff88800d9b6360 index:0x1
flags: 0xfffffc0000000()
raw: 000fffffc0000000 dead000000000100 dead000000000200 ffff88800d9b6360
raw: 0000000000000001 0000000000000000 00000000ffffffff
page dumped because: non-NULL mapping
CPU: 0 PID: 676 Comm: kswapd0 Not tainted 4.20.0-rc6-dgc+ #915
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1 04/01/2014
Call Trace:
dump_stack+0x67/0x90
bad_page.cold.116+0x8a/0xbd
free_pcppages_bulk+0x4bf/0x6a0
free_unref_page_list+0x10f/0x1f0
shrink_page_list+0x49d/0xf50
shrink_inactive_list+0x19d/0x3b0
shrink_node_memcg.constprop.77+0x398/0x690
? shrink_slab.constprop.81+0x278/0x3f0
shrink_node+0x7a/0x2f0
kswapd+0x34b/0x6d0
? node_reclaim+0x240/0x240
kthread+0x11f/0x140
? __kthread_bind_mask+0x60/0x60
ret_from_fork+0x24/0x30
Disabling lock debugging due to kernel taint
....
The failures are from anyway that frees pages and empties the
per-cpu page magazines, so it's not a predictable failure or an easy
to debug failure.
generic/038 is a reliable reproducer of this problem - it has a 9 in
10 failure rate on one of my test machines. Failure on other
machines have been at random points in fstests runs but every run
has ended up tripping this problem. Hence generic/038 was used to
bisect the failure because it was the most reliable failure.
It is too close to the 4.20 release (not to mention holidays) to
try to diagnose, fix and test the underlying cause of the problem,
so reverting the commit is the only option we have right now. The
revert has been tested against a current tot 4.20-rc7+ kernel across
multiple machines running sub-page block size XFs filesystems and
none of the bad page state failures have been seen.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Cc: Piotr Jaroszynski <pjaroszynski@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use __print_symbolic to print the scrub type in ftrace output.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Use __print_symbolic to print the btree type in ftrace output.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Move XFS_INODE_FORMAT_STR to libxfs so that we don't forget to keep it
updated, and add necessary TRACE_DEFINE_ENUM.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Move XFS_AG_BTREE_CMP_FORMAT_STR to libxfs so that we don't forget to
keep it updated, and TRACE_DEFINE_ENUM the values while we're at it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
ftrace's __print_symbolic() has a (very poorly documented) requirement
that any enum values used in the symbol to string translation table be
wrapped in a TRACE_DEFINE_ENUM so that the enum value can be encoded in
the ftrace ring buffer. Fix this unsatisfied requirement.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Use %pS instead of %pF in ftrace strings so that we record the actual
function address instead of the function descriptor.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
If the file system has been shut down or is read-only, then
ext4_write_inode() needs to bail out early.
Also use jbd2_complete_transaction() instead of ext4_force_commit() so
we only force a commit if it is needed.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Some time back, nfsd switched from calling vfs_fsync() to using a new
commit_metadata() hook in export_operations(). If the file system did
not provide a commit_metadata() hook, it fell back to using
sync_inode_metadata(). Unfortunately doesn't work on all file
systems. In particular, it doesn't work on ext4 due to how the inode
gets journalled --- the VFS writeback code will not always call
ext4_write_inode().
So we need to provide our own ext4_nfs_commit_metdata() method which
calls ext4_write_inode() directly.
Google-Bug-Id: 121195940
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and the file
system has metadata checksums enabled, we shouldn't try to get the
inode, discover the checksum is invalid, and then declare the file
system as being inconsistent.
This can be reproduced by creating a test file system via "mke2fs -t
ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
directory, and then running the following program.
#define _GNU_SOURCE
#include <fcntl.h>
struct handle {
struct file_handle fh;
unsigned char fid[MAX_HANDLE_SZ];
};
int main(int argc, char **argv)
{
struct handle h = {{8, 1 }, { 12, }};
open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
return 0;
}
Google-Bug-Id: 120690101
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
In ext4_expand_extra_isize_ea(), we calculate the total size of the
xattr header, plus the xattr entries so we know how much of the
beginning part of the xattrs to move when expanding the inode extra
size. We need to include the terminating u32 at the end of the xattr
entries, or else if there is uninitialized, non-zero bytes after the
xattr entries and before the xattr values, the list of xattr entries
won't be properly terminated.
Reported-by: Steve Graham <stgraham2000@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Some servers require that the setinfo matches the exact size,
and in this case compounding changes introduced by
commit c2e0fe3f5a ("cifs: make rmdir() use compounding")
caused us to send 8 bytes (padded length) instead of 1 byte
(the size of the structure). See MS-FSCC section 2.4.11.
Fixing this when we send a SET_INFO command for delete file
disposition, then ends up as an iov of a single byte but this
causes problems with SMB3 and encryption.
To avoid this, instead of creating a one byte iov for the disposition value
and then appending an additional iov with a 7 byte padding we now handle
this as a single 8 byte iov containing both the disposition byte as well as
the padding in one single buffer.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Core changes:
- Parse the 4BAIT SFDP section
- Add a bunch of SPI NOR entries to the flash_info table
- Add the concept of SFDP fixups and use it to fix a bug on MX25L25635F
- A bunch of minor cleanups/comestic changes
NAND core changes:
- kernel-doc miscellaneous fixes.
- Third batch of fixes/cleanup to the raw NAND core impacting various
controller drivers (ams-delta, marvell, fsmc, denali, tegra, vf610):
* Stopping to pass mtd_info objects to internal functions
* Reorganizing code to avoid forward declarations
* Dropping useless test in nand_legacy_set_defaults()
* Moving nand_exec_op() to internal.h
* Adding nand_[de]select_target() helpers
* Passing the CS line to be selected in struct nand_operation
* Making ->select_chip() optional when ->exec_op() is implemented
* Deprecating the ->select_chip() hook
* Moving the ->exec_op() method to nand_controller_ops
* Moving ->setup_data_interface() to nand_controller_ops
* Deprecating the dummy_controller field
* Fixing JEDEC detection
* Providing a helper for polling GPIO R/B pin
Raw NAND chip drivers changes:
- Macronix:
* Flagging 1.8V AC chips with a broken GET_FEATURES(TIMINGS)
Raw NAND controllers drivers changes:
- Ams-delta:
* Fixing the error path
* SPDX tag added
* May be compiled with COMPILE_TEST=y
* Conversion to ->exec_op() interface
* Dropping .IOADDR_R/W use
* Use GPIO API for data I/O
- Denali:
* Removing denali_reset_banks()
* Removing ->dev_ready() hook
* Including <linux/bits.h> instead of <linux/bitops.h>
* Changes to comply with the above fixes/cleanup done in the core.
- FSMC:
* Adding an SPDX tag to replace the license text
* Making conversion from chip to fsmc consistent
* Fixing unchecked return value in fsmc_read_page_hwecc
* Changes to comply with the above fixes/cleanup done in the core.
- Marvell:
* Preventing timeouts on a loaded machine (fix)
* Changes to comply with the above fixes/cleanup done in the core.
- OMAP2:
* Pass the parent of pdev to dma_request_chan() (fix)
- R852:
* Use generic DMA API
- sh_flctl:
* Converting to SPDX identifiers
- Sunxi:
* Write pageprog related opcodes to the right register: WCMD_SET (fix)
- Tegra:
* Stop implementing ->select_chip()
- VF610:
* Adding an SPDX tag to replace the license text
* Changes to comply with the above fixes/cleanup done in the core.
- Various trivial/spelling/coding style fixes.
SPI-NAND drivers changes:
- Removing the depreacated mt29f_spinand driver from staging.
- Adding support for:
* Toshiba TC58CVG2S0H
* GigaDevice GD5FxGQ4xA
* Winbond W25N01GV
Several ioctl structs change size between native 32-bit (ia32) and x32
applications, because x32 follows the native 64-bit (amd64) integer
alignment rules and uses 64-bit time_t. In these instances, the ioctl
number changes so userspace simply gets -ENOTTY. This scenario can be
handled by simply adding more cases.
Looking at the different ioctls implemented here:
- All the ones marked 'No size or alignment issue on any arch' should
presumably all be fine.
- All the ones under BROKEN_X86_ALIGNMENT are different under integer
alignment rules. Since x32 matches amd64 here, we just need both
sets of cases handled.
- XFS_IOC_SWAPEXT has both integer alignment differences and time_t
differences. Since x32 matches amd64 here, we need to add a case
which calls the native implementation.
- The remaining ioctls have neither 64-bit integers nor time_t, so
x32 matches ia32 here and no change is required at this level. The
bulkstat ioctl implementations have some pointer chasing which is
handled separately.
Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The bulkstat family of ioctls are problematic on x32, because there is
a mixup of native 32-bit and 64-bit conventions. The xfs_fsop_bulkreq
struct contains pointers and 32-bit integers so that matches the native
32-bit layout, and that means the ioctl implementation goes into the
regular compat path on x32.
However, the 'ubuffer' member of that struct in turn refers to either
struct xfs_inogrp or xfs_bstat (or an array of these). On x32, those
structures match the native 64-bit layout. The compat implementation
writes out the 32-bit version of these structures. This is not the
expected format for x32 userspace, causing problems.
Fortunately the functions which actually output these xfs_inogrp and
xfs_bstat structures have an easy way to select which output format
is required, so we just need a little tweak to select the right format
on x32.
Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
While inspecting the ioctl implementations, I noticed that the compat
implementation of XFS_IOC_ATTRLIST_BY_HANDLE does not do exactly the
same thing as the native implementation. Specifically, the "cursor"
does not appear to be written out to userspace on the compat path,
like it is on the native path.
This adjusts the compat implementation to copy out the cursor just
like the native implementation does. The attrlist cursor does not
require any special compat handling. This fixes xfstests xfs/269
on both IA-32 and x32 userspace, when running on an amd64 kernel.
Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Fixes: 0facef7fb0 ("xfs: in _attrlist_by_handle, copy the cursor back to userspace")
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Before this patch, function do_grow would not reserve enough journal
blocks in the transaction to unstuff jdata files while growing them.
This patch adds the logic to add one more block if the file to grow
is jdata.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
The typos accumulate over time so once in a while time they get fixed in
a large patch.
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the error handling block, err holds the return value of either
btrfs_del_root_ref() or btrfs_del_inode_ref() but it hasn't been checked
since it's introduction with commit fe66a05a06 (Btrfs: improve error
handling for btrfs_insert_dir_item callers) in 2012.
If the error handling in the error handling fails, there's not much left
to do and the abort either happened earlier in the callees or is
necessary here.
So if one of btrfs_del_root_ref() or btrfs_del_inode_ref() failed, abort
the transaction, but still return the original code of the failure
stored in 'ret' as this will be reported to the user.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since cloning and deduplication are no longer Btrfs specific operations, we
now have generic code to handle parameter validation, compare file ranges
used for deduplication, clear capabilities when cloning, etc. This change
makes Btrfs use it, eliminating a lot of code in Btrfs and also fixing a
few bugs, such as:
1) When cloning, the destination file's capabilities were not dropped
(the fstest generic/513 tests this);
2) We were not checking if the destination file is immutable;
3) Not checking if either the source or destination files are swap
files (swap file support is coming soon for Btrfs);
4) System limits were not checked (resource limits and O_LARGEFILE).
Note that the generic helper generic_remap_file_range_prep() does start
and waits for writeback by calling filemap_write_and_wait_range(), however
that is not enough for Btrfs for two reasons:
1) With compression, we need to start writeback twice in order to get the
pages marked for writeback and ordered extents created;
2) filemap_write_and_wait_range() (and all its other variants) only waits
for the IO to complete, but we need to wait for the ordered extents to
finish, so that when we do the actual reflinking operations the file
extent items are in the fs tree. This is also important due to the fact
that the generic helper, for the deduplication case, compares the
contents of the pages in the requested range, which might require
reading extents from disk in the very unlikely case that pages get
invalidated after writeback finishes (so the file extent items must be
up to date in the fs tree).
Since these reasons are specific to Btrfs we have to do it in the Btrfs
code before calling generic_remap_file_range_prep(). This also results
in a simpler way of dealing with existing delalloc in the source/target
ranges, specially for the deduplication case where we used to lock all
the pages first and then if we found any dealloc for the range, or
ordered extent, we would unlock the pages trigger writeback and wait for
ordered extents to complete, then lock all the pages again and check if
deduplication can be done. So now we get a simpler approach: lock the
inodes, then trigger writeback and then wait for ordered extents to
complete.
So make btrfs use generic_remap_file_range_prep() (XFS and OCFS2 use it)
to eliminate duplicated code, fix a few bugs and benefit from future bug
fixes done there - for example the recent clone and dedupe bugs involving
reflinking a partial EOF block got a counterpart fix in the generic
helper, since it affected all filesystems supporting these operations,
so we no longer need special checks in Btrfs for them.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
extent_readpages processes all pages in the readlist in batches of 16,
this is implemented by a single for loop but thanks to an if condition
the loop does 2 things based on whether we've filled the batch or not.
Additionally due to the structure of the code there is an additional
check which deals with partial batches.
Streamline all of this by explicitly using two loops. The outter one is
used to process all pages while the inner one just fills in the batch
of 16 (currently). Due to this new structure the code guarantees that
all pages are processed in the loop hence the code to deal with any
leftovers is eliminated.
This also enable the compiler to inline __extent_readpages:
./scripts/bloat-o-meter fs/btrfs/extent_io.o extent_io.for
add/remove: 0/1 grow/shrink: 1/0 up/down: 660/-820 (-160)
Function old new delta
extent_readpages 476 1136 +660
__extent_readpages 820 - -820
Total: Before=44315, After=44155, chg -0.36%
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The first step of the rebalance process ensures there is 1MiB free on
each device. This number seems rather small. And in fact when talking to
the original authors their opinions were:
"man that's a little bonkers"
"i don't think we even need that code anymore"
"I think it was there to make sure we had room for the blank 1M at the
beginning. I bet it goes all the way back to v0"
"we just don't need any of that tho, i say we just delete it"
Clearly, this piece of code has lost its original intent throughout the
years. It doesn't really bring any real practical benefits to the
relocation process.
Additionally, this patch makes the balance process more lightweight by
removing a pair of shrink/grow operations which are rather expensive for
heavily populated filesystems. This is mainly due to shrink requiring
relocating block groups, involving heavy use of the btree.
The intermediate shrink/grow can fail and leave the filesystem in a
middle state that would need to be changed back by the user.
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
If we create a snapshot of a snapshot currently being used by a send
operation, we can end up with send failing unexpectedly (returning
-ENOENT error to user space for example). The following diagram shows
how this happens.
CPU 1 CPU2 CPU3
btrfs_ioctl_send()
(...)
create_snapshot()
-> creates snapshot of a
root used by the send
task
btrfs_commit_transaction()
create_pending_snapshot()
__get_inode_info()
btrfs_search_slot()
btrfs_search_slot_get_root()
down_read commit_root_sem
get reference on eb of the
commit root
-> eb with bytenr == X
up_read commit_root_sem
btrfs_cow_block(root node)
btrfs_free_tree_block()
-> creates delayed ref to
free the extent
btrfs_run_delayed_refs()
-> runs the delayed ref,
adds extent to
fs_info->pinned_extents
btrfs_finish_extent_commit()
unpin_extent_range()
-> marks extent as free
in the free space cache
transaction commit finishes
btrfs_start_transaction()
(...)
btrfs_cow_block()
btrfs_alloc_tree_block()
btrfs_reserve_extent()
-> allocates extent at
bytenr == X
btrfs_init_new_buffer(bytenr X)
btrfs_find_create_tree_block()
alloc_extent_buffer(bytenr X)
find_extent_buffer(bytenr X)
-> returns existing eb,
which the send task got
(...)
-> modifies content of the
eb with bytenr == X
-> uses an eb that now
belongs to some other
tree and no more matches
the commit root of the
snapshot, resuts will be
unpredictable
The consequences of this race can be various, and can lead to searches in
the commit root performed by the send task failing unexpectedly (unable to
find inode items, returning -ENOENT to user space, for example) or not
failing because an inode item with the same number was added to the tree
that reused the metadata extent, in which case send can behave incorrectly
in the worst case or just fail later for some reason.
Fix this by performing a copy of the commit root's extent buffer when doing
a search in the context of a send operation.
CC: stable@vger.kernel.org # 4.4.x: 1fc28d8e2e: Btrfs: move get root out of btrfs_search_slot to a helper
CC: stable@vger.kernel.org # 4.4.x: f9ddfd0592: Btrfs: remove unused check of skip_locking
CC: stable@vger.kernel.org # 4.4.x
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When initializing the security xattrs, we are holding a transaction handle
therefore we need to use a GFP_NOFS context in order to avoid a deadlock
with reclaim in case it's triggered.
Fixes: 39a27ec100 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With my delayed refs patches in place we started seeing a large amount
of aborts in __btrfs_free_extent:
BTRFS error (device sdb1): unable to find ref byte nr 91947008 parent 0 root 35964 owner 1 offset 0
Call Trace:
? btrfs_merge_delayed_refs+0xaf/0x340
__btrfs_run_delayed_refs+0x6ea/0xfc0
? btrfs_set_path_blocking+0x31/0x60
btrfs_run_delayed_refs+0xeb/0x180
btrfs_commit_transaction+0x179/0x7f0
? btrfs_check_space_for_delayed_refs+0x30/0x50
? should_end_transaction.isra.19+0xe/0x40
btrfs_drop_snapshot+0x41c/0x7c0
btrfs_clean_one_deleted_snapshot+0xb5/0xd0
cleaner_kthread+0xf6/0x120
kthread+0xf8/0x130
? btree_invalidatepage+0x90/0x90
? kthread_bind+0x10/0x10
ret_from_fork+0x35/0x40
This was because btrfs_drop_snapshot depends on the root not being
modified while it's dropping the snapshot. It will unlock the root node
(and really every node) as it walks down the tree, only to re-lock it
when it needs to do something. This is a problem because if we modify
the tree we could cow a block in our path, which frees our reference to
that block. Then once we get back to that shared block we'll free our
reference to it again, and get ENOENT when trying to lookup our extent
reference to that block in __btrfs_free_extent.
This is ultimately happening because we have delayed items left to be
processed for our deleted snapshot _after_ all of the inodes are closed
for the snapshot. We only run the delayed inode item if we're deleting
the inode, and even then we do not run the delayed insertions or delayed
removals. These can be run at any point after our final inode does its
last iput, which is what triggers the snapshot deletion. We can end up
with the snapshot deletion happening and then have the delayed items run
on that file system, resulting in the above problem.
This problem has existed forever, however my patches made it much easier
to hit as I wake up the cleaner much more often to deal with delayed
iputs, which made us more likely to start the snapshot dropping work
before the transaction commits, which is when the delayed items would
generally be run. Before, generally speaking, we would run the delayed
items, commit the transaction, and wakeup the cleaner thread to start
deleting snapshots, which means we were less likely to hit this problem.
You could still hit it if you had multiple snapshots to be deleted and
ended up with lots of delayed items, but it was definitely harder.
Fix for now by simply running all the delayed items before starting to
drop the snapshot. We could make this smarter in the future by making
the delayed items per-root, and then simply drop any delayed items for
roots that we are going to delete. But for now just a quick and easy
solution is the safest.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When debugging some weird extent reference bug I suspected that we were
changing a snapshot while we were deleting it, which could explain my
bug. This was indeed what was happening, and this patch helped me
verify my theory. It is never correct to modify the snapshot once it's
being deleted, so mark the root when we are deleting it and make sure we
complain about it when it happens.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
